Air-lock system for a continuously operated vertical cement kiln



M y 1955 F. P. SOMOGYI AIR-"LOCK SYSTEM FOR A CONTINUOUSLY OPERATED VERTICAL CEMENT KILN Filed April 26, 1950 INVENTOR FRANCIS PAUL SOMOGYI ATTORNEY United States atent ice AIR-LOCK SYSTEM FGR ACONTINUOUSLY UPERATED VERTICAL CEMENT KEN Francis Paul Sornogyi, London, England Application April 26, 1950, Serial No. 158,105

Claims priority, application Great Britain July 18, 1949 3 Claims. (Cl. 214-17) This invention relates to an air-lock system for a conpends to a large extent on the air conditions prevailing i within the kiln, egress of air through the chute is undesirable and detrimental and should be reduced to a mini mum.

in this connection it is known to form an air-lock between the kiln and the discharge end of the chute, by pivotally mounting at least. two lap-gates within the chute, the gates being arranged to open and close in succession so that at least one gate is always closed.

In practice however, difliculty is experienced in completely closing the gates, against the continuous flow of material, due to material becoming wedged between the gate and its seat. Because of this, air is allowed to escape t'herethrough at a relatively high velocity, carrying with it a large amount of dust which causes a considerable wear not only in the chute itself but to the machined surfaces of the gates. Furthermore, the machined surfaces of the gates are also subjected to considerable abrasion due to being in contact with the flow of material. In consequence, the efficiency of the kiln is impaired and heavy expenditure incurred in making good the wear caused by the above adverse conditions.

According to the present invention there is provided an air-lock system for a continuously operated vertical cement kiln having a chute with an inclined floor down which material discharged from the kiln flows, the said system comprising at least two flap-gates adapted to close air-tightly the chute and arranged to open and close in succession so that one flap-gate at least is always closed to prevent egress of air through the chute, and an additional gate provided in front of each flap-gate and adapted to be moved into the closed position before the associated flap-gate closes in order to arrest the flow of material and to ailow the load-free closing of said flap-gates and to be moved into the open position after or together with the opening movement of the associated flap-gate to keep the material out of contact with said flap-gates during the closing movement of said flap-gates and to allow the ilow of material to be resumed while both the said additional gate and its associated flap-gate are open.

By virtue of the above arrangement the flap-gates can be closed more easily and a substantially satisfactory airlock ensured. Furthermore, abrasion of the flap-gates and wear in the chute itself is considerably reduced whereby a substantial saving in time and material is effected and the efliciency of the kiln is improved.

The additional gate may be conveniently designed as a segmental gate pivotally mounted in the chute and adapt- 2 ed to swing out of a well in the inclined floor and to move across the chute to arrest the flow of material.

Preferably each flap-gate is protected by a depending trap-plate against which the associated segmental gate closes when it swings out of the well.

A preferred embodiment of the invention will now be described by way of example with reference to the ac companying drawing in which:

Fig. 1 shows a vertical cross-section through a discharge chute for a vertical cement kiln provided with an airlock system according to the invention, and

Fig. 2 is a fragmentary detail plan view showing the actuating shaft for the gates.

Referring now to the drawing, a vertical cement kiln (not shown) has a chute 1 disposed at the bottom thereof. The chute has an inclined floor 2 down which material discharged from the kiln flows, the receiving end of the chute being in communication with the bottom of the kiln. A segmental gate 3 is pivotally mounted in the chute 1 near the upper end thereof and arranged to swing out of a well 4 in the floor 2 to arrest the flow of material and subsequently to swing back into the well to allow the How of material to be resumed. The leading edges 3a of the radial sides of the segmental gate 3 in the closed position, abut the underside of a depending pivotal trap-plate 5 hinged to the chute 1 by hinge straps 6. A flap-gate 7 is associated with the segmental gate 3 and is pivotally mounted in the chute below the segmental gate 3 in the direction of flow of material down the chute, and arranged to close against a seat 8 in order to prevent egress of air therethrough. A second segmental gate 9, a pivotal trap-plate 10 hinged to the chute by hinge straps 11, and a second flap-gate 12 associated to the segmental gate 9 are disposed in the chute near the lower end thereof in like relationship and in a similar manner to the segmental gate 3, the trap-plate 5 and the flap-gate 7 described above. In the latter case the segmental gate 9 is arranged to swing out of and into a Well 14 in the floor 2 and the leading edges 9a of the radial sides of the segmental gate 9, in the closed position, abut the under-side of the depending trap-plate 10 whilst the flap-gate 12 is arranged to close against a seat 13. The trap-plates 5 and 10 serve to protect the flap-gates 7 and 12 respectively from being damaged by large pieces of material passing down the chute, the trap-plates being so arranged to arrest such large pieces of material and to guide them through the flap-gates at a substantially reduced speed.

The segmental gates 3 and 9 and the flap-gates 7 and 12 are each counter-balanced by weights 15, 16, 17 and 18 respectively, each weight being so positioned as to assist in closing the gate with which it is associated and thereafter to hold the gate against its seat.

The material discharged from the kiln through the chute 1 is fed to a suitable conveyor 19.

The gates 3, 7, 9, 12 are each independently actuated by a cam mechanism through crank levers 20, 21, 22 and 23 respectively connected by links 24, 25, 26, 27 to camshaped levers 28, 29, 30, 31 mounted on a common spindle 32. The cam-shaped levers are actuated from a revolving actuating shaft 33 by rollers mounted eccentrically of the shaft between spaced discs on the shaft. For the sake of clarity the drawing shows only the roller 34 co-operating with the cam-shaped lever 29.

Referring to Fig. 2 of the drawing, it will be seen that the roller 34 is mounted between discs 35, 36 on the actu ating shaft 33.

The gates 3, 7, 9, 12 each remain closed for more than half a complete working cycle, i. e. for more than half a complete revolution of the actuating shaft 33. At the commencement of each cycle the flap-gate 7 begins to open and is again a little closed before the end of the first half-cycle. The segmental gate 3 begins to open a little after the flap-gate '7 and closes before the flapgate 7. The flow of material to flap-gate 7 is therefore, not resumed until the flap-gate is already partly open, and the flow of material is again arrested before me ilapgate 7 closes, so that material does not come into contact with the flap-gate 7. In an analogous manner the fiapgate 11?, connne; to at the beginning of the second half-cycle and is again fully closed a little before the end of the second half cycle, whilst the segmental gate 9 begins to open a little after the flap-gate azd is again fully closed a little before the flap-gate 12. The segmental gates 3 and 9 thus shield the flap-gates 7 and 12 from contact with the material.

In the instantaneous position shown in the drawing it will be observed that the segmental gate 9 and the gate 12 are closed, the flap-gate 7 is in the open position and about to commence its closing movement whilst the segmental gate 3 is already part-way closed.

Having now particularly described and ascertained the nature of my said invention and in what manner the same is to be performed, I declare that What 1 claim is:

1. An air-lock system for a continuously operated vertical cement kiln having a chute with an inclined floor down which the material discharged from the kiln flows,

the said system comprising two flap-gates mounted in the chute, operating means adapted to open and to close said flap-gates in succession so that one flap-gate at least is always closed to prevent egress of air through the chute,

an additional gate provided in front of each flap-gate, and 3 the said additional gate and its associated flap-gate are L open.

2. An air-lock system for a continuously operated vertical cement kiln having a chute with an inclined floor down which the material discharged from the kiln flows, the said system comprising two flap-gates mounted in the chute, operating means adapted to open and to close said ilap-gates in succession so that one flap-gate at least is always closed to prevent egress of air through the chute,

an additional gate pivotally mounted in the chute in front of each flap-gate and having the form of a cylinder segment, and operating means adapted to move each additional gate into the closed position before the associated flap-gate closes in order to arrest the flow of material and to allow the load-free closing of said flap-gates, and to move said additional gate into the open position after or together with the opening movement of the associated flan to lac-op the material out or contact with said 1 flap-gates during the closing movement of said flap-gates and to allow the flow of material to be resumed while both the said additional gate and its associated flap-gate are open, and a well in the inclined floor of the chute suited to receive the additional gate when said gate is moved to free the passage through said chute.

3. An air-lock system for a continuously operated vertical cement kiln having a chute with an inclined tloor down which the material discharged from the kiln flows, the said system comprising two flap-gates mounted in the chute, operating means adapted to open and to close said flap-gates in succession so that one fiapgate at least is always closed to prevent egress of air through the chute, an additional gate provided in front of each flap-gate, operating means adapted to move each additional gate into the closed position before the associated flap-gate closes in order to arrest the flow of material and to allow the load-free closing of said flap-gates, and to move said additional gate into the open position after or together with the opening movement of the associated flapgate to keep the material out of contact with said flapgates during the closing movement of said flap-gates and to allow the fiow of material to be resumed While both the said additional gate and its associated flap-gate are open, and an inctined pivotal trap-plate in front of each flap-gate, each trap-plate being so arranged that the leading edge of said additional gate bears in its closed position against the free edge of said trap-plate.

References Cited in the file of this patent UNITED STATES PATENTS 387,001 McCutcheon July 31, 1888 998,994 Smith July 25, 191 1 2,151,514 Heinen Mar. 21, 1939 F0 ElGN PATENTS 225,205 Great Britain Nov. 11, 1924 548,498 Germany Apr. 13, 1932 871,273 France Jan. 10, 1942 

